Outcome domains for studies of acute and chronic gout.

Discussion and voting at OMERACT 9 confirmed 5 essential domains for outcomes of acute gout: pain, joint swelling, joint tenderness, patient global assessment and activity limitations. For studies in chronic gout 7 essential domains are: serum urate, acute gout attacks, tophus burden, health-related quality of life, activity limitations, pain, and patient global assessment. Implications of patient perspectives, discretionary domains for specific studies, measurement instruments and a possible responder index are under study.